1. Field of the Invention
The present invention relates to a video processing apparatus capable of reproducing arbitrary viewpoint video (free-viewpoint video) corresponding to a viewpoint from which a user wishes to view the video, as well as a control method for such an apparatus.
2. Description of the Related Art
With the start of digital broadcasting, televisions that are capable of receiving digital broadcasts (that is, digital televisions) are spreading. At present, the age of full-scale advent of the digital broadcasting is met, and extensive research and development into different types of next-generation broadcasting systems is being carried out. In particular, “arbitrary viewpoint video (free-viewpoint video)”, in which a user (viewer) can freely specify the camera viewpoint, is gathering attention. Arbitrary viewpoint video corresponding to a camera viewpoint specified by a user is generated using video shot from multiple (a plurality of) viewpoints.
Japanese Patent Laid-Open No. 2007-150747 is known as a technique related to switching between the display of arbitrary viewpoint video and video actually shot by a camera (camera video). Japanese Patent Laid-Open No. 2007-150747 discloses a receiving apparatus that receives a broadcast stream containing broadcast video and viewpoint information for the broadcast video. When a request to distribute the arbitrary viewpoint video has been made, this receiving apparatus uses the viewpoint information of the broadcast video extracted from the broadcast stream as the initial value of the viewpoint of arbitrary viewpoint video.
Because arbitrary viewpoint video is generated by synthesizing video obtained by multiple cameras from different viewpoints, the image quality thereof is generally not as high as the image quality of video from the individual cameras used to generate the arbitrary viewpoint video. Accordingly, in the case where the video from the camera is video from the viewpoint requested by a user, it is thought that the user will feel a higher sense of satisfaction with the video from the camera than the arbitrary viewpoint video, in terms of the image quality. However, a user that is viewing arbitrary viewpoint video cannot know if there is video from a camera that has a viewpoint close to the viewpoint requested by the user. Although the technique disclosed in Japanese Patent Laid-Open No. 2007-150747 does discuss switching from a broadcast video (video from a camera) to arbitrary viewpoint video, it is not possible to recognize the relationship between a viewpoint requested by a user and the viewpoint of the video from the camera while the user is viewing the arbitrary viewpoint video.